Does etiology really matter for epilepsy surgery outcome?

Abstract Objective To select patients with drug resistant epilepsy following up in Pediatrics Neurology Outpatient Clinic of Children's Hospital, Ain Shams University who are candidates for epilepsy surgery and to detect outcome of epilepsy surgery in such children as regards seizures control. Methods This prospective study was conducted over a period of 36 months and comprises of 3 stages. Stage 1 includes selection of candidates for epilepsy surgery and preoperative evaluation. Evaluation included clinical assessment, video EEG, MRI epilepsy protocol. Stage 2 include surgery phase where decision of surgery was made by a multidisciplinary team. Stage 3 includes post-operative evaluation as regards Seizures frequency, Seizures Severity using Chalfont score, Engel Epilepsy Surgery Outcome Scale and the International League Against Epilepsy (ILAE) outcome classification. Data was tabulated and analyzed with SSPS package for windows. Results 17 patients underwent epilepsy surgery. Results revealed significant decrease in seizures frequency and severity at 6 and 12 months after surgery. As regards Engel Epilepsy Surgery Outcome Scale 11 (64.7%) patients were class I at 12 months. As regards the ILAE outcome classification 10 (58.8%) patients are class 1 at 12 months. Conclusions epilepsy surgery can be a hope for patients with drug resistant epilepsy who are well selected and evaluated preoperatively. New studies on larger number and for longer duration are recommended.

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Association of fast ripples on intracranial EEG and outcomes after epilepsy surgery

Neurology ◽

10.1212/wnl.0000000000010468 ◽

2020 ◽

Vol 95 (16) ◽

pp. e2235-e2245

Author(s):

Päivi Nevalainen ◽

Nicolás von Ellenrieder ◽

Petr Klimeš ◽

François Dubeau ◽

Birgit Frauscher ◽

...

Keyword(s):

Epilepsy Surgery ◽

Slow Wave Sleep ◽

Seizure Outcome ◽

Incomplete Resection ◽

Epileptogenic Zone ◽

Poor Prognostic Factor ◽

Individual Level ◽

Poor Outcome ◽

Surgery Outcome ◽

The Individual

ObjectiveTo examine whether fast ripples (FRs) are an accurate marker of the epileptogenic zone, we analyzed overnight stereo-EEG recordings from 43 patients and hypothesized that FR resection ratio, maximal FR rate, and FR distribution predict postsurgical seizure outcome.MethodsWe detected FRs automatically from an overnight recording edited for artifacts and visually from a 5-minute period of slow-wave sleep. We examined primarily the accuracy of removing ≥50% of total FR events or of channels with FRs to predict postsurgical seizure outcome (Engel class I = good, classes II–IV = poor) according to the whole-night and 5-minute analysis approaches. Secondarily, we examined the association of low overall FR rates or absence or incomplete resection of 1 dominant FR area with poor outcome.ResultsThe accuracy of outcome prediction was highest (81%, 95% confidence interval [CI] 67%–92%) with the use of the FR event resection ratio and whole-night recording (vs 72%, 95% CI 56%–85%, for the visual 5-minute approach). Absence of channels with FR rates >6/min (p = 0.001) and absence or incomplete resection of 1 dominant FR area (p < 0.001) were associated with poor outcome.ConclusionsFRs are accurate in predicting epilepsy surgery outcome at the individual level when overnight recordings are used. Absence of channels with high FR rates or absence of 1 dominant FR area is a poor prognostic factor that may reflect suboptimal spatial sampling of the epileptogenic zone or multifocality, rather than an inherently low sensitivity of FRs.Classification of evidenceThis study provides Class II evidence that FRs are accurate in predicting epilepsy surgery outcome.

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Temporal Lobe Epilepsy Surgery: Outcome, Complications, and Late Mortality Rate in 215 Patients

Epilepsia ◽

10.1046/j.1528-1157.2002.33800.x ◽

2002 ◽

Vol 43 (2) ◽

pp. 170-174 ◽

Cited By ~ 123

Author(s):

V. Salanova ◽

O. Markand ◽

R. Worth

Keyword(s):

Mortality Rate ◽

Temporal Lobe Epilepsy ◽

Temporal Lobe ◽

Epilepsy Surgery ◽

Late Mortality ◽

Surgery Outcome

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Subtraction peri-ictal SPECT is predictive of extratemporal epilepsy surgery outcome

Neurology ◽

10.1212/wnl.55.11.1668 ◽

2000 ◽

Vol 55 (11) ◽

pp. 1668-1677 ◽

Cited By ~ 151

Author(s):

T. J. O'Brien ◽

E. L. So ◽

B. P. Mullan ◽

G. D. Cascino ◽

M. F. Hauser ◽

...

Keyword(s):

Epilepsy Surgery ◽

Ictal Spect ◽

Surgery Outcome

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Epilepsy Surgery Series: A Study of 502 Consecutive Patients from a Developing Country

Epilepsy Research and Treatment ◽

10.1155/2014/286801 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8

Author(s):

Abdulaziz Alsemari ◽

Faisal Al-Otaibi ◽

Salah Baz ◽

Ibrahim Althubaiti ◽

Hisham Aldhalaan ◽

...

Keyword(s):

Temporal Lobe ◽

Epilepsy Surgery ◽

Intractable Epilepsy ◽

Research Centre ◽

Mesial Temporal Sclerosis ◽

Brain Scans ◽

Temporal Epilepsy ◽

Dual Pathology ◽

Surgery Outcome ◽

Postoperative Seizure

Purpose. To review the postoperative seizure outcomes of patients that underwent surgery for epilepsy at King Faisal Specialist Hospital & Research Centre (KFSHRC). Methods. A descriptive retrospective study for 502 patients operated on for medically intractable epilepsy between 1998 and 2012. The surgical outcome was measured using the ILAE criteria. Results. The epilepsy surgery outcome for temporal lobe epilepsy surgery (ILAE classes 1, 2, and 3) at 12, 36, and 60 months is 79.6%, 74.2%, and 67%, respectively. The favorable 12- and 36-month outcomes for frontal lobe epilepsy surgery are 62% and 52%, respectively. For both parietal and occipital epilepsy lobe surgeries the 12- and 36-month outcomes are 67%. For multilobar epilepsy surgery, the 12- and 36-month outcomes are 65% and 50%, respectively. The 12- and 36-month outcomes for functional hemispherectomy epilepsy surgery are 64.2% and 63%, respectively. According to histopathology diagnosis, mesiotemporal sclerosis (MTS) and benign CNS tumors had the best favorable outcome after surgery at 1 year (77.27% and 84.3%, resp.,) and 3 years (76% and 75%, resp.,). The least favorable seizure-free outcome after 3 years occurred in cases with dual pathology (66.6%). Thirty-four epilepsy patients with normal magnetic resonance imaging (MRI) brain scans were surgically treated. The first- and third-year epilepsy surgery outcome of 17 temporal lobe surgeries were (53%) and (47%) seizure-free, respectively. The first- and third-year epilepsy surgery outcomes of 15 extratemporal epilepsy surgeries were (47%) and (33%) seizure-free. Conclusion. The best outcomes are achieved with temporal epilepsy surgery, mesial temporal sclerosis, and benign CNS tumor. The worst outcomes are from multilobar surgery, dual pathology, and normal MRI.

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Epidemic models characterize seizure propagation and the effects of epilepsy surgery in individualized brain networks based on MEG and invasive EEG recordings

10.1101/2021.09.20.21263459 ◽

2021 ◽

Author(s):

Ana P Millan ◽

Elisabeth CW van Straaten ◽

Cornelis J Stam ◽

Ida A Nissen ◽

Sander Idema ◽

...

Keyword(s):

Epilepsy Surgery ◽

Brain Networks ◽

Patient Specific ◽

Model Parameters ◽

Seizure Freedom ◽

Seed Region ◽

Epidemic Spreading ◽

Surgery Outcome ◽

Seizure Propagation ◽

Resection Area

Background Epilepsy surgery is the treatment of choice for drug-resistant epilepsy patients. However, seizure-freedom is currently achieved in only 2/3 of the patients after surgery. In this study we have developed an individualized computational model based on functional brain networks to explore seizure propagation and the efficacy of different virtual resections. Eventually, the goal is to obtain individualized models to optimize resection strategy and outcome. Methods We have modelled seizure propagation as an epidemic process using the susceptible-infected (SI) model on individual functional networks derived from presurgical MEG. We included 10 patients who had received epilepsy surgery and for whom the surgery outcome at least one year after surgery was known. The model parameters were tuned in order to reproduce the patient-specific seizure propagation patterns as recorded with invasive EEG. We defined a personalized search algorithm that combined structural and dynamical information to find resections that maximally decreased seizure propagation for a given resection size. The optimal resection for each patient was defined as the smallest resection leading to at least a $90\%$ reduction in seizure propagation. Results The individualized model reproduced the basic aspects of seizure propagation for 9 out of 10 patients when using the resection area as the origin of epidemic spreading, and for 10 out of 10 patients with an alternative definition of the seed region. We found that, for 7 patients, the optimal resection was smaller than the resection area, and for 4 patients we also found that a resection smaller than the resection area could lead to a 100% decrease in propagation. Moreover, for two cases these alternative resections included nodes outside the resection area. Conclusion Epidemic spreading models fitted with patient specific data can capture the fundamental aspects of clinically observed seizure propagation, and can be used to test virtual resections in silico. Combined with optimization algorithms, smaller or alternative resection strategies, that are individually targeted for each patient, can be determined with the ultimate goal to improve surgery outcome.

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